Natural product can be an entire or part of organism such as a plant, an animal or a microorganism. Extract, exudate and pure compound isolated from a plant, an animal or a microorganism can also be regarded as a natural product. Natural products are the good resources of nutraceuticals and medicines. This course introduced the biosynthesis pathways of natural products, the isolation and purification methods, the classification and bioactivities of natural products. The topics include coumarins, lignans, flavonoids, quinones, glycosides, carbohydrates, essential oils, steroids, terpenoids, and alkaloids.